# What's the Lowest Common Multiple (LCM) of 7 and 8?

Feb 1, 2018

56

#### Explanation:

write down the multiple of 7, n then 8. choose the one that's common and the least. :)

multiples of 7 $\implies 7 , 14 , 21 , 28 , 35 , 42 , 49 , \textcolor{red}{56} , 63. \ldots$
multiples of 8 $\implies 8 , 16 , 24 , 32 , 40 , 48 , \textcolor{red}{56} , 64 , 72. \ldots$

so the lcm, I.e. least common multiple of 7 and 8 is, 56.

Feb 6, 2018

$7 \times 8 = 56$
They have no common factors apart from $1$

#### Explanation:

$7 \mathmr{and} 8$ are consecutive numbers.

Therefore they have no common factors apart from $1$

The first time they will share a common multiple is with their own product.

$7 \times 8 = 56$

Looking at their prime factors:

$\text{ "8 = " } 2 \times 2 \times 2$
$\text{ } 7 = 7$

$L C M = 7 \times 2 \times 2 \times 2 = 56$